Natural isotopic abundance

{
  "id": "MLC-T-CHM-013325",
  "term": "Natural isotopic abundance",
  "field": "Chemistry",
  "definition": "The relative proportion of each stable isotope of an element as it occurs in nature. These abundances are relatively constant across the Earth, although minor variations can exist due to geological or biological processes. For example, carbon-12 accounts for approximately 98.9% of natural carbon, while carbon-13 accounts for about 1.1%.",
  "subject": "Analytical Chemistry",
  "see_also": [
    "isotopic abundance"
  ],
  "references": [
    "PAC, 1982, 54, 1533. 'Glossary of terms used in nuclear analytical chemistry (Provisional)' on page 1535 (https://doi.org/10.1351/pac198254081533)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/natural-isotopic-abundance/"
}